Drill-extractor.



' l B. F. BBTTS.

DRILL EXTRAGTOR.

APPLICATION FILED 00T.10,1910.

Patented Apr. 23, 1912.

Inventor.

witnesseex 7 ENE BENJAMAN F. BETTS, OF GOLDROAD, ARIZONA.

DRILL-EXTRACTOR.

Specification of Letters Patent.

Application filed. October 10, 1910.

Patented Apr. 23, 1912.

Serial No. 586,203.

.T 0 all whom it may concern:

Be it known that I, BENJAMAN F. Burrs, a citizen of the United States, residing at Goldroad, county of Mojave, State of Arizona, have invented new and useful Improvements in Drill-Extractors, of which the following is a specification.

This invention relates to mining and particularly to the operation of drills.

The object of the invention is to provide improved means for extracting a drill bit which has become stuck in the bore which it is forming, and the invention contemplates the use of the power of the drill itself to extract the bit.

In the drawing forming a part of the annexed specification Figure 1 is a horizontal section showing a gallery in a mine or quarry in which a drilling operation is progressing, and illustrating the manner in which my mechanism is applied to facilitate the withdrawal of the drill bit. This view shows the drill chuck in section. Fig. 2 is a vertical section through a clamp which is secured to the shank of the drill bit in order to facilitate its withdrawal, the drill bit being indicated in dotted lines. This section is taken on the line 2-2 :of Fig. 1. Fig. 3 is a section through a fulcrum block which constitutes a feature of the invention, taken on the line 33 of Fig. 1, certain parts being shown in elevation. Fig. 4c is a perspective of the yoke by means of which the power of the drill is applied to the extracting lever to withdraw the bit.

Referring more particularly to the parts,

5 represents the walls of the gallery in which the drilling operation is progressing. The drill 6 which may be operated by compressed air or steam is mounted upon a horizontal stopping bar 7, which is secured between the side walls 8 of the gallery.

The drilling bit 9 is indicated at the left and is supposed to have been stuck in the bore which it isforming, the drill 6 indicated in dotted lines having been supported on the bar 7 in alinement with the bit, as indicated. It should be understood that the drill 6 is mounted to slide on the stopping bar 7 in the usual manner.

My mechanism for extracting the bit comprises a lever 10 which is provided with a longitudinal slot 11 at an intermediate point and by means of this slot the lever is movably mounted in the fulcrum block 12, said fulcrum block being in the form of a sleeve as indicated in Fig. 3, through which passes a fulcrum post 13. The lever is attached to the fulcrum block by means of a pin or bolt 14, and in order to receive the lever the block is formed with an enlarged slot 15 through which the lever passes as indicated.

The post 13 is provided at its inner end, that is at the end adjacent to the wall 5 with a point 16 which is adapted to engage the wall as will be readily understood. The post 13 is of square or rectangular cross section and one of its edges is provided with a plurality of notches 17, said notches being of substantially V shape, and presenting abrupt shoulders 18 on the side toward the pin 16. At a suitable point near its forward or inner end the block 12 is provided with a pivot pin 19 which passes transversely under the block and on this pivot pin there is attached the arms 20 of a stirrup 21, said stirrup having a cross bar 22 connecting the arms 20, and this cross bar is adapted to engage with the notches 17 as indicated. By swinging the stirrup upwardly into the position in which it is shown in dotted lines in Fig. 3 the block can be released from the post so as to enable it to be adjusted in or out of the post. The outer end of the post is provided with a cross pin or stud 23 which prevents the block from becoming displaced. The forward end of the post 13 is provided with a lug 24 for a similar purpose. This post is held up adjacent to the drill bit and parallel with the drill bit as shown in Fig. 1 and the lever 10 is then secured to the drill bit 9 by means of a clamp 25, said clamp being pivotally attached to the end of the lever by a pivot pin 26 as shown in Fig. 2. This clamp 25 is in the form of a split sleeve having a body section 27, and a cap or cover section 28, the drill bit being clamped between the two sections, as illustrated. In order to clamp the cap 28 against the body section a U bolt 29 is provided which straddles the clamp, and the legs of which are threaded so as to receive clamping nuts 30,

passing through openings in suitable lugs 31 against which the nuts 30 seat, as indicated. In order to increase the rigidity of the pin 26, the body section 27 of the clamp is formed with a rudimentary socket 32, which receives the end of the lever, as shown, and across this socket the bolt 26 is mounted.

Under the cross bar 33 of the U bolt 29 a wedge 34 is provided which is adapted to be driven inwardly to clamp the cap 28 against the body section of the clamp. The small end of this wedge is provided with an outwardly projecting toe 35, which normally prevents the wedge from becoming detached unless the nuts 30 are removed. The lever 10 presents a long arm at its right end as shown in Fig. 1, and at the extremity of thls long arm the material is turned downwardly to form a retaining toe 36; and on the lever, near this retaining toe a yoke 37 is mounted, the forks 38 of the said yoke being connected by a removable cross pin 89 which retains the yoke on the lever, as indicated. This yoke is formed with a shank 4.0 which is adapted to be inserted in the chuck 41 of the drill when the drill is removed from alinement with the bit, and adjusted into position to operate upon the lever, as shown.

With the drill mounted as shown in Fig. 1, the operating fluid is admitted through the hose 42 so as to drive the drill and strike against the shank 40. This drives the yoke toward the wall 5 and through the lever 10 imparts a force to the drill bit 9 at the clamp 25, which tends to withdraw the bit. By sliding the block 12 to any position on the post 18, the position of the fulcrum pin 14 can be adjusted to suit the position of the drill and the clamp. The drill 6 is provided with a feed screw 43 by means of which the body of the drill may be adjusted toward the wall 5 or away from it, by means of a crank 44 and this facilitates the removal of the drill from the bit before sliding it on the stopping bar 7 to operate upon the lever. The drill is provided with a valve 45 or stop cock operated by a lever 46 for admitting air or steam to operate the drill, as will be readily understood.

With this mechanism it will be evident that if the drill bit becomes stuck, the drill cylinder can be readily adjusted and set up in connection with the lever 10 and the other parts to enable the power of the drill to be applied to extract the bit. Attention is called to the slot 11 and to the fact that the use of the slot at this point permits a sliding movement between the lever and the post. This enables the lever to adapt itself to the straight line movement of the drill bit, as it is withdrawn.

The invention is particularly useful with power drills that simply strike the bit and do not reciprocate it.

hat I claim is:

1. A mechanism of the class described, comprising in combination with a power drill having a detachable bit, of means for withdrawing the bit from its work comprising a clamp adapted to be fastened to the drill, a fulcrum capable of arrangement adjacent thereto, a lever having movable connection with said clamp and said fulcrum, and means operable by the drill for forcing the lever to withdraw the bit.

2. In combination with a power drill having a removable bit, a mechanism for withdrawing the bit comprising a clamp adapted to grip the bit, an adjustable fulcrum arranged adjacent thereto, a lever having movable engagement with the said clamp and the said fulcrum, and a member adapted to be driven by the said drill and having movable engagement with the said lever for operating the latter to withdraw the bit from its work.

3. In combination, a power drill having a removable bit adapted to be driven into a mine wall, means for supporting said power drill in alinement with said drill bit and at a point removed from alinement therewith, a clamp adapted to be attached to the drill bit, a lever pivotally attached to said clamp, a member engaging said lever and cooperating with the power drill to impart movement to said clamp, and an adjustable fulcrum block connected with said lever and disposed adjacent to said drill bit.

4. A mechanism for withdrawing drill bits comprising in combination with an adjustable drill and a movable drill bit, of a lever, a bit clamp pivotally mounted upon one end thereof, said lever being formed with a slot intermediate its length, a fulcrum device movably engaging said slot, and a thrust member having a yoke for engaging the free end of the lever, the said thrust member being adapted to be operated by the drill for causing the lever to withdraw the bit from a hole bored thereby.

5. In combination with a power-drill and a removable bit adapted to be operated thereby, of mechanism for withdrawing the bit from its work comprising a lever, a bit engaging clamp pivoted upon one end of the lever, and having means for causing it to firmly grip the bit at any point along its length, adjustable fulcrum devices carried by said lever, the said lever having an elongated slot for accommodating itself to the positions of the said fulcrum, and a yoke member having a lever engaging bearing adapted to press upon the free end of the lever, the said yoke member being provided with lever retaining means for preventing In Witness that I claim the foregoing I its becoming disengaged from the yoke have hereunto subscribed my name this 30th member, and means for supporting the day of September, 1910.

power drill so that it may be disconnected BENJAMAN F. BETTS. 5 from the drill and be made to operate the lVitnesses:

said yoke member for causing the lever to GEO. B. AYERS,

Withdraw the bit. CHESTER A. WILSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. 0. 

